Boole failed

 From:  Frenchy Pilou (PILOU)
10128.4 In reply to 10128.3 
You must have only solids for easy Boolean operations...
So before make something with your Sphere

Make each part as solid :something like : separate , Planar extremities Join or Boolean Union
so you have 2 big parts solid - Union them you = have only one part

You can now make any operations you wish with the Sphere (solid)
here an Union and a Difference

EDITED: 1 Feb 2021 by PILOU